Relating to the Extender EF 1.4x II, Canon says this converter is compatible with:
"This tele extender can be used with fixed focal length lenses 135mm and longer (except the 135mm f/2.8 Softfocus lens), and the EF 70-200 f/2.8L, 70-200 f/2.8L IS, 70-200 f/4.0L, 70-200 f/4.0L IS USM, and 100-400 f/4.5-5.6L IS zoom lenses."
I do not believe that the Canon teleconverters will even mount to the Canon EF 70-300mm, f/4-5.6 IS USM without the potential for damage. This is due to an protruding front element in the teleconverter which will conflict with the rear element of the 70-300mm lens.
I do believe that some of the Tamron teleconverters will mount on that lens, but the image quality suffers fairly dramatically. (For instance I have tried the Tamron "F" series 1.4x teleconverter on the Tamron 75-300mm, f4-f5.6 LD Macro (1:3.9) and the results were less than satisfying.)
The other problem is that you lose AF with most Canon cameras since the 1.4x teleconverters lose 1 stop of effective aperture. Most cameras will only AF with lenses of aperture f5.6 or faster. (The Canon 1D/1Ds series will AF through f8 however.)
The 2x teleconverters just compound the problem since they lose 2 stops of effective aperture.
Relating to the Extender EF 1.4x II, Canon says this converter is compatible with:
"This tele extender can be used with fixed focal length lenses 135mm and longer (except the 135mm f/2.8 Softfocus lens), and the EF 70-200 f/2.8L, 70-200 f/2.8L IS, 70-200 f/4.0L, 70-200 f/4.0L IS USM, and 100-400 f/4.5-5.6L IS zoom lenses."
I do not believe that the Canon teleconverters will even mount to the Canon EF 70-300mm, f/4-5.6 IS USM without the potential for damage. This is due to an protruding front element in the teleconverter which will conflict with the rear element of the 70-300mm lens.
I do believe that some of the Tamron teleconverters will mount on that lens, but the image quality suffers fairly dramatically. (For instance I have tried the Tamron "F" series 1.4x teleconverter on the Tamron 75-300mm, f4-f5.6 LD Macro (1:3.9) and the results were less than satisfying.)
The other problem is that you lose AF with most Canon cameras since the 1.4x teleconverters lose 1 stop of effective aperture. Most cameras will only AF with lenses of aperture f5.6 or faster. (The Canon 1D/1Ds series will AF through f8 however.)
The 2x teleconverters just compound the problem since they lose 2 stops of effective aperture.
The canon TCs are the most incompatible. Sigmas, Kenko, and tamron are all good substitutes. There are sites that crowd-source compatabilities because these manufacturers list a small line of lenses.
In the end just go to a camera shop and try it with the sigma or tamron. Don't even waste the time with the canon.
Canon Gear: 5D MkII, 30D, 85 1.2 L, 70-200 2.8 IS L, 17-40mm f4 L, 50 1.4, 580EX, 2x 580EXII, Canon 1.4x TC, 300 f4 IS L, 100mm 2.8 Macro, 100-400 IS L Other Gear: Olympus E-PL1, Pan 20 1.7, Fuji 3D Camera, Lensbaby 2.0, Tamron 28-75 2.8, Alien Bees lighting, CyberSyncs, Domke, HONL, FlipIt.
~ Gear Pictures
... In the end just go to a camera shop and try it with the sigma or tamron. Don't even waste the time with the canon.
If you have the Canon 70-200mm zooms, any of them, the Canon TCs do a better job than the high end Tamron or Kenko TCs that I tried. The EF 135mm, f2L USM is also excellent used with the Canon EF 1.4x II. It did not test well with the Kenko Pro I tried.
I know of at least 2 reviewers that claim good results with the high-end Tamron SP and Kenko Pro converters, but my tests were not so good and I wound up returning the others and going with Canon.
Oddly I like the Tamron "F" 1.4x very nicely when used with the Canon EF 50mm, f1.4 USM.
Like John says, test for yourself and decide. No one else knows your personal needs better than yourself.
If you have the Canon 70-200mm zooms, any of them, the Canon TCs do a better job than the high end Tamron or Kenko TCs that I tried.
Sorry. I did not mean to imply that the canon TC was poor. It's the best optically out of the third party alternatives. However it's a bad choice for anyone looking to maximize compatability such as the OP.
Canon Gear: 5D MkII, 30D, 85 1.2 L, 70-200 2.8 IS L, 17-40mm f4 L, 50 1.4, 580EX, 2x 580EXII, Canon 1.4x TC, 300 f4 IS L, 100mm 2.8 Macro, 100-400 IS L Other Gear: Olympus E-PL1, Pan 20 1.7, Fuji 3D Camera, Lensbaby 2.0, Tamron 28-75 2.8, Alien Bees lighting, CyberSyncs, Domke, HONL, FlipIt.
~ Gear Pictures
I currently have a canon 70-300 mm 4-5.6IS lens and I am wondering if I buy a teleconverter if it will work with this lens.
Thanks!
Nope, they only work with L lenses.
Tamron, Kenko, Sigmas work with all EF mount lenses IIRC.
However, having said that I would not recommend a tc for that lens as you may lose AF and also there could be significant degradation in image quality.
I have both 1.4 and 2 X Canon TC, it works only with L lens. Not compatible to other EF lens.
Remember some previous thread (a year ago), someone suggest to cut the rubber from the Canon TCs in order to make it work with other EF lens. I won't do it!
Comments
"This tele extender can be used with fixed focal length lenses 135mm and longer (except the 135mm f/2.8 Softfocus lens), and the EF 70-200 f/2.8L, 70-200 f/2.8L IS, 70-200 f/4.0L, 70-200 f/4.0L IS USM, and 100-400 f/4.5-5.6L IS zoom lenses."
I do not believe that the Canon teleconverters will even mount to the Canon EF 70-300mm, f/4-5.6 IS USM without the potential for damage. This is due to an protruding front element in the teleconverter which will conflict with the rear element of the 70-300mm lens.
I do believe that some of the Tamron teleconverters will mount on that lens, but the image quality suffers fairly dramatically. (For instance I have tried the Tamron "F" series 1.4x teleconverter on the Tamron 75-300mm, f4-f5.6 LD Macro (1:3.9) and the results were less than satisfying.)
The other problem is that you lose AF with most Canon cameras since the 1.4x teleconverters lose 1 stop of effective aperture. Most cameras will only AF with lenses of aperture f5.6 or faster. (The Canon 1D/1Ds series will AF through f8 however.)
The 2x teleconverters just compound the problem since they lose 2 stops of effective aperture.
Moderator of the Cameras and Accessories forums
The canon TCs are the most incompatible. Sigmas, Kenko, and tamron are all good substitutes. There are sites that crowd-source compatabilities because these manufacturers list a small line of lenses.
In the end just go to a camera shop and try it with the sigma or tamron. Don't even waste the time with the canon.
Other Gear: Olympus E-PL1, Pan 20 1.7, Fuji 3D Camera, Lensbaby 2.0, Tamron 28-75 2.8, Alien Bees lighting, CyberSyncs, Domke, HONL, FlipIt.
~ Gear Pictures
If you have the Canon 70-200mm zooms, any of them, the Canon TCs do a better job than the high end Tamron or Kenko TCs that I tried. The EF 135mm, f2L USM is also excellent used with the Canon EF 1.4x II. It did not test well with the Kenko Pro I tried.
I know of at least 2 reviewers that claim good results with the high-end Tamron SP and Kenko Pro converters, but my tests were not so good and I wound up returning the others and going with Canon.
Oddly I like the Tamron "F" 1.4x very nicely when used with the Canon EF 50mm, f1.4 USM.
Like John says, test for yourself and decide. No one else knows your personal needs better than yourself.
Moderator of the Cameras and Accessories forums
Sorry. I did not mean to imply that the canon TC was poor. It's the best optically out of the third party alternatives. However it's a bad choice for anyone looking to maximize compatability such as the OP.
Other Gear: Olympus E-PL1, Pan 20 1.7, Fuji 3D Camera, Lensbaby 2.0, Tamron 28-75 2.8, Alien Bees lighting, CyberSyncs, Domke, HONL, FlipIt.
~ Gear Pictures
Tamron, Kenko, Sigmas work with all EF mount lenses IIRC.
However, having said that I would not recommend a tc for that lens as you may lose AF and also there could be significant degradation in image quality.
Remember some previous thread (a year ago), someone suggest to cut the rubber from the Canon TCs in order to make it work with other EF lens. I won't do it!
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